Relay



July 1l, 1939. w, F, KANNENBERG 2,165,798

RELAY Filed Jan.` l21, 1957 s sheets-sheet 1 ATORNEV July 11 1939 w. F.KANNENBERG 2,165,798

RELAY Filed Jan. 2l, 1937 3 Sheets-Sheet 2 Ff (k12 F/c. 3

W F. KANNE NBE RG www ATTORNEY July 1.1, 1939. w. F. KANNENBERG2,165,798

' ATTORNEY Patented July 11, 1939 UNITED STATES PATENT OFFiCE RELAYApplication January 21, 1937, Serial No. 121,600

10 Claims.

This invention relates to electromagnetic devices and more particularlyto relays of the meter type.

The object of the invention is to provide a relay of the meter typewhich shall be sensitive and accurate and shall have very positivecontact pressure.

The relay in accordance with the invention comprises a fixed permanentmagnet supported along the diameter and within an annular eld yoke andan armature coil surrounding the permanent magnet and so mounted onspindles that it may swing between the poles of the magnet and the innerperiphery of the yoke. Each spindle is pivoted in a fixed bearing and isprovided with a helical restoring spring. One of the spindles carries acontact arm which in each of its eX- treme positions of movement engageswith a xed terminal. The restoring springs are so arranged that thearmature coil is normally held in a neutral position with respect to thepermanent magnet and the contact arm is positioned at a point midwaybetween the fixed terminals.

To insure a positive pressure between the contact arm and either of thexed terminals when the armature coil reaches the eXtreme of its movementin either direction, two split iron rings are adjustably positioned onthe inner periphery of the yoke and serve to decrease the air-gapsbetween the yoke and the poles of the permanent magnet. These rings areso positioned that when the armature coil approaches a position in whichthe contact arm engages with one of the xed terminals, it enters thereduced air-gap areas be- 35 tween the ring and the poles of thepermanent magnet and thus the magnetic pull on the coil is increased tothereby increase the contact pressure between the contact arm and thexed terminal with which it is engaged. Since the an- 40 nular rings aresplit like piston rings they may be readily moved along the innerperiphery of the yoke to positions where they are most effective andthen maintain themselves set in the positions to which they have beenmoved.

As alternative constructions, shoes may be placed on the poles of thepermanent magnet in lieu of rings on the inner periphery of the yoke, orthe permanent magnet may be laminated With the outer laminationsextensible toward the inner periphery of the yoke thereby affordingmeans for adjustably decreasing the width of the air-gaps through whichthe armature coil swings.

For a clearer understanding of the invention reference may be had tothe. following' detailed description taken in connection with theaccompanying drawings in which:

Fig. 1 is a plan view of a relay embodying the invention;

Fig. 2 is asectional view taken on line 2 2 of 5 Fig. 1;

Fig. 3 is a sectional View taken on line 3-3 of Fig. 1;

Fig. 4 is an enlarged sectional view of the lefthand armature coilspindle and bearing as viewed in Fig. 3;

Fig. 5 is an enlarged sectional view of the righthand armature coilspindle and bearing as viewed in Fig. 3; l

Fig. 6 is a sectional View corresponding to Fig. 2, with parts of therelay omitted, showing modified forms of the armature coil andadjustable yoke rings;

Fig. 7 is a sectional View corresponding to Fig. 2, with parts of therelay omitted, showing a further modiication of the yoke, permanentmagnetl and adjustable magnet shoes;

Fig. 8 is a plan view of a modiiied form of the permanent magnet for usein the structure of Fig. 7; and

Fig. 9 is a side view of the permanent magnet shown in Fig. 8.

Referring now more in detail to the drawings, Figs. l to 5 inclusive,illustrate one embodiment of the relay in accordance with the invention.The annular field yoke I is mounted on a base IBI of Bakelite or othersuitable insulating material and is secured thereto by bolts it. whichpass through the base and through the yoke. The base is annular inconformation and is provided with a web 03 having a centrally disposedcylindrical support HM on which are disposed a plurality of bar magnets05 which form a permanent magnet assembly for the relay. The bar magnetsmay be made of cobalt steel or other suitable permanent magnet materialhaving a high remanence and high coercive force.

The bar magnets are held in place in grooves in the upper surface of thecylindrical support |04 as most clearly shown in Fig. 3, by two clampingplates I of insulating material. These clamping plates are provided withgrooves in which the terminal posts l'l are adjustably positioned. Bolts08 extend through apertures in the bases of posts iol, plates |06 andthe web 263 of base lil! for securing the bar magnets in place and forholding the terminal posts in adjusted position. The terminal posts |01are electrically connected through the bolts |03 and straps i to bindingposts lill which are secured in the 55 annular walls of the base IGI.Each of the terminal posts |571 has a terminal screw III, provided witha knurled adjusting head, threaded through the biiurcated upper endthereof. For clamping the biiurcated portions of the ends of each posttogether i'or holding the terminal screw III in its adjusted position,screws I|2 are provided.

The bar magnets 35 are provided With arcuate ends forming a compositearc about the center of yoke |35 about which the movable coil I3 swings.This coil consists of a plurality of convolutions of insulated wirewound on a channel-shaped frame I|4 of aluminum or other suitablematerial. The frame is of substantially the same configuration as thepermanent magnet assembly and is cemented or otherwise secured at thecenters of its parallel sides to spindles ||5 and IIS which carry pivotpoints adapted to be journalled in jewelled bearings carried by thebearing screws IVI and IIB. The bearing screws III and ||8 are threadedthrough the upper bifurcated ends of supports IIS and I2@ which aresecured at their lower ends to the web |53 of base IBI by bolts I2I and|22. The bearing support IIS is electrically connected through the bolt|2| and strap I 23 to the binding post |24 which is secured in theannular wall of base IIII, as shown in Fig. 3. For holding each bearingscrew IIT or IIS in adjusted position, screws |25 are provided forclamping the bifurcated ends of the supports IISi and |23 together. l

Surrounding the spindle I|5 isl a light helical restoring spring |25,the inner end of which is secured to a bracket Hl mounted on the spindle||5 and the outer end of which is secured to an adjustable bracket |23mounted on the bearing screw III. The bracket |23 is clamped against thebearing support ||3 by the lock nut |29 and may be rotated on the screwI |'|,when the nut |23 is loosened, to adjust the tension of the spring|26. The bracket |27, together with the contact arm |33, is clamped uponthe spindle ||5 by the lock nut I 3|. The contact arm 35 is positionedin alignment with and between the contact ends of the terminal screws II and is electrically connected through the spindle ||5, bearing screwIII, support IIS, screw |2I and strap |23 to binding post |24. Thus,upon the movement of the coil I3 the contact arm |33 mayengageeither ofthe terminal screws III as the current in the coil II3 varies betweenpredetermined limits.

Surrounding the spindle ||6 is a second light helical restoring spring|32 wound oppositely to spring |25, the inner end of which is secured toa bracket |33 mounted on the spindle ||6 and the outer end of which issecured to an adjustable bracket |34 mounted on the bearing screw H8.The bracket |34 is clamped against the bearing support |23 by the locknut |35 and may be rotated on the screw H3, when lock nut |35 isloosened, to adjust the tension of spring |32. The bracket |33, togetherwith washers |35 and |3'I', is clamped upon the spindle IE by the locknut |33. The washers |33 and |3'I are insulated from each other and fromthe spindle ||6 by insulating washers |39 and insulating sleeve |45 asmost clearly shown in Fig. 5. The washers |36 and |37 are electricallyconnected to the terminals of the coil ||3 and also by ilexibleconnections |4I and |42 to the upper ends of posts |43 and |44 which arein turn connected to the binding posts |45 and |45 mounted in theannular wall of the base Ii. The circuit for coil ||3 thus extends fromthe binding post |45 through post |43, flexible connection |4|, washer|36, through the coil, washer |31, iiexible connection |42, post |44 tobinding post |45.

For adjusting the width of the air-gaps between the poles of thepermanent magnet assembly and the inner peripheral surface of the fieldyoke IIB, two iron rings III'I and |43 are provided. Each ring is splitlike a piston ring, as shown at |43, and is so tensioned as to grip theinner surface of the yoke. The inner surfaces of the rings are bevelledon an arc concentric to the arcuate ends of the permanent magnetassembly. Due to their split construction the rings may be adjustablypositioned on the inner surface of the yoke |30 at such points thereonthat they afford reduced air-gaps between the yoke and the poles of thepermanent magnet assembly into which the ends of the coil H3 move as thecoil approaches the eXtreme of its swinging movement in eitherdirection. With the airgaps thus reduced the force exerted on the coilI3 is increased as the coil approaches either extreme of its movementand thereby the contact arm |33, which follows the swinging movement ofthe coil, is brought into firm engagement with the terminal screw withwhich it engages.

In Fig. 6 modied forms of the coil and iron field rings are disclosed.In accordance with this modication, the iield yoke |33 is identical withthat disclosed in Fig. 2, but the permanent magnet assembly |55 is madeslightly shorter to accommodate a coil H3 wound in pancake form. Theadjustable iron rings |4'I' and |43 are also changed in cross-section topresent narrow or line surfaces |50 and I5| to the ends of coil H3 asthe coil reaches the extreme of its swinging movement in eitherdirection. To simplify the disclosure the other elements of the modifiedrelay structure have not been illustrated, but would be identical withthose disclosed in Figs. i to 5 inclusive.

Fig. 7 illustrates a further modication of the relay structure. Inaccordance with this modification the base ||3| is identical with thatdisclosed in Fig. 2, but the eld yoke |35 is slightly modified toprovide a spherical inner surface |52 within which the coil II3 swings,there being a very narrow air-gap between the surface |52 and the endsof the coil. The permanent magnet assembly |05 is made shorter and witharcuate ends concentric to the inner surface |52 of the yoke Hifi. Inthis modication shoes |41 and |48 of magnetic material are adjustablymounted on the permanent magnet assembly and have their outer surfacesbeveled on an arc concentric to the surface |52 of the yoke |00. Theshoes may be adjustably positioned on the permanent magnet assembly atsuch points thereon that they afford reduced air-gaps between thesurface |52 of the yoke and the poles of the permanent magnet assembly.To simplify the disclosure, the other elements of the modified relaystructure have not been illustrated, but would be identical with thosedisclosed in Figs. 1 to 5 inclusive.

Figs. 8 and 9 illustrate a further modiiication. of the permanent magnetassembly suitable for use with the field yoke |30 and coil I3 of Fig. 7.In accordance with this modiiication, the permanent magnet assemblycomprises a plurality of horizontally disposed bar magnets, two insidemagnets |53 and two outside magnets each divided into two similarsections 54 and |55. Each of the sections |54 and |55 is provided with alongitudinally extending slot |55 aligned with holes in the insidemagnets |53 through which the clamping bolts |08 pass for holding themagnet assembly on the cylindrical support |04 of the base The sections|54 an |55 are also provide with transversely extending cam slots |51 inwhich studs |58 and |59 carried by the discs |60 and il engage.

The discs are preferably of brass or other nonmagnetic material, disc|6| being disposed in a depression in the upper end of cylindricalsupport |04 of the base and underlying the two lower magnet sections |54and |55 and the disc |60 being disposed above the two upper magnetsections |54 and |55. The discs are journalled for rotation as a unit onthe central bolt |62 extending upwardly through the support |04 andmagnet assembly by the sleeve |63 of nonmagnetic material. The ends ofthe sleeve |63 are provided with squared portions |64 which fit intosquared openings in the discs |60 and |6| whereby when the disc |60 isturned by the knurled knob |65 attached thereto', the rotation of disc|60 is transmitted through sleeve |63 to disc |6|. The upper threadedend of bolt |62 is provided with a knurled lock nut |66 by means ofwhich the discs |60 and IBI are held in their adjusted positions.

By means of the engagement of studs |58 and carried by the discs |60 and|6| in the cam slots |51', the magnet section |54 and |55 may beextended beyond the ends of magnets |53, as disclosed, or withdrawntoward each other into the positions indicated by the dotted lines ofFig. 8, through the rotation of discs |60 and I6| by the knob |65A Thelongitudinal slots |56 in the magnet sections |54 and |55 permit of thismovement when the clamping bolts |08 and the central bolt |62 areloosened. By this construction of the permanent magnet assembly it ispossible to widen or narrow the air-gaps between the pole ends of thepermanent magnet assembly and the inside surface of the eld yoke at thepoints where the ends of the armature coils reach their extreme ofmovement in either direction.

From the foregoing description it will be apparent that a relaystructure of the meter type is provided which is sensitive and accuratein, operation and in which a very positive engagement of the contacts isattained with no sacrifice to the sensitivity.

What is claimed is:

l. An electromagnetic device comprising a magnet, a yoke of magneticmaterial surrounding said magnet and forming air-gaps wish the polesthereof, a rotatably supported coil surrounding said magnet androtatable upon its energizatio-n through said air-gaps, and means foradjusting the width of said air-gaps at points adjacent to` the extremesof movement of said coil.

2. An electromagnetic device comprising a magnet, a yoke of magneticmaterial surrounding said magnet and forming air-gaps with the polesthereof, a rotatably supported coil surrounding said magnet androtatable upon its energization through said air-gaps, `and members ofmagnetic material adjustably supported in said air-gaps at pointsadjacent to the extremes of movement of said coil.

3. An electromagnetic device comprising a magnet, a yoke of magneticmaterial surrounding said magnet and forming air-gaps with the polesthereof, a rotatably supported coil surrounding said magnet androtatable upon its energization through said air-gaps, and split ringsof magnetic material adjustably supported on the inner surface of saidyoke for reducing the width of said air-gaps at points adjacent to theextremes ofmovement of said coil.

4. An electromagnetic device comprising a magnet, a yoke of magneticmaterial surrounding said magnet and forming air-gaps with the polesthereof, a rotatably supported coil surrounding said magnet androtatable upon its energization through said air-gaps, and rings ofmagnetic material adjustably supported on the inner surface of said yokefor reducing the width of said air-gaps at points adjacent to theextremes of movement of said coil.

5. An electromagnetic device comprising a magnet, a yoke of magneticmaterial surrounding said magnet and forming air-gaps with the polesthereof, a rotatably supported coil surrounding said magnet androtatable upon its energization through said air-gaps, said coil beingwound in pancake form, and split rings of magnetic material adjustablysupported on the inner surface of said yoke for reducing the width ofsaid airgaps and of such cross-section as to present narrow air-gapsurfaces to the edges of said coil at points adjacent to the extremes ofmovement of said coil.

6. An electromagnetic device comprising a magnet, a yoke of magneticmaterial surrounding said magnet and forming air-gaps with the palesthereof, a rotatably supported coil surrounding said magnet androtatable upon its energization through said air-gaps, and shoes ofmagnetic material adjustably supported on the poles of said magnet forreducing the air-gaps at points adjacent to the extremes of movement ofsaid coil.

7. An electromagnetic device comprising a plurality of bar magnetsforming a permanent magnet assembly, a yoke of magnetic materialsurrounding said magnet assembly and forming airgaps with the polesthereof, a rotatably supported coil surrounding said magnet assembly androtatable upon its energization through said airgaps, and means foradjustably moving certain of said bar magnets for reducing the width ofthe air-gaps at points adjacent to the extremes of movement of saidcoil.

8. An electromagnetic device comprising a plurality of superimposed barmagnets forming a permanent magnet assembly, the outer ones of said barmagnets each being divided into two sections, a yoke of magneticmaterial surrounding said magnet assembly and forming air-gaps with thepoles thereof, a rotatably supported coil surrounding said magnetassembly and rotatable upon its energization through said air-gaps, andmeans for moving the sections of each of said outside magnets toward oraway from each other for adjusting the width of the air-gaps at pointsadjacent to the extremes of movement of said coil.

9. An electromagnetic device comprising a plurality of superimposed barmagnets forming a permanent magnet assembly, the outer ones of said barmagnets each being divided into two slidable sections, a yoke ofmagnetic material surrounding said magnet assembly and forming airgapswith the poles thereof, a rotatably supported coil surrounding saidmagnet assembly and rotatable upon its energization through saidairgaps, and means for sliding the sections of each of said outsidemagnets toward or away from each other for adjusting the width of theairgaps at points adjacent the extremes of movement of said coil, saidmeans comprising rotatable cams.

10 air-gaps, and means for sliding the sections of each of said outsidemagnets toward or away from each other for adjusting the Width of theair-gaps at points adjacent to the extremes of movement of said coil,said means comprising two interconnected rotatable discs associatedrespectively with the two sections of each outside magnet, and studscarried by each disc and engaged in cam slots in the magnet sectionswith which said disc is associated.

WALTER F. KANNENBERG.

